GEO 101 Ch 3

Which of the following groups of silicate minerals exhibits a single strong cleavage in one direction? A. sheet silicates B. single-chain silicates C. framework silicates D. independent tetrahedra silicates

A

Which of the following statements is FALSE? Crystals: A. are formed by the high-temperature, extremely rapid process known as solid-state diffusion. B. grow outward from a seed. C. display symmetry. D. have an orderly internal arrangement of atoms arranged in a lattice pattern.

A

Identify the FALSE statement. A. The faces of a crystal need not be the same size throughout the crystal, but the angle of intersection between comparable faces is the same throughout. B. Polymorphs of the same mineral have the same crystal shape because they contain the same basic atoms bonded in the same way. C. There is an angle of 120° between each crystal face of the hexagonal column of a quartz crystal. D. Crystals can be a variety of geometric shapes, including cubes, trapezoids, pyramids, octahedrons, hexagons, columns, blades, and needles.

B

Identify the FALSE statement. Silicates: A. have the silicon-oxygen tetrahedron as their structural unit. B. are a large category of minerals and include the common minerals calcite and dolomite. C. are classified on the basis of how the tetrahedrons join and share oxygen atoms. D. are a major component of continental crust.

B

The tendency of a mineral to break and produce smooth, curving, shell-shaped surfaces is termed: A. cleavage. B. conchoidal fracture. C. streak. D. luster.

B

Which of the following is NOT a mineral? A. an oyster shell, because it's not crystalline B. oil, because it's a liquid, not a solid C. pyrite, because it's a chemical compound D. a gold nugget, because it's a native metal

B

Which of the following is a mineral? A. glass B. salt (NaCl) C. sugar (formula C6H12O6) D. amber (tree sap)

B

Calcite and aragonite minerals that constitute clam shells are examples of which method of mineral formation? A. solidification of a melt B. precipitation from a solution C. biomineralization D. solid-state diffusion

C

Graphite is: A. harder than glass. B. the polymorph of galena. C. the "lead" in the pencil you write with. D. pure silicon.

C

There are two physical properties of minerals that both result in smooth, flat surfaces with specific angles between them. The first property is externally visible and is the result of how the mineral forms; the second is inherently internal and is the result of breaking a sample of the mineral. These properties are called: A. cleavage and hardness. B. cleavage and crystal habit. C. crystal habit and cleavage. D. hardness and cleavage.

C

Which is NOT a physical property commonly used in the field to identify minerals? A. color B. luster C. X-ray diffraction D. specific gravity

C

Which of the following statements about gemstones is FALSE? A. A gemstone is a mineral that has value because of its rarity and beauty. B. Many gemstones come from pegmatites, which are particularly coarse-grained igneous rocks. C. In order to be considered precious or semiprecious, a gemstone must be transparent. D. Ruby is a gemstone variety of the common mineral corundum.

C

Which of the following statements is FALSE? Diamonds: A. of industrial quality are used as abrasives. B. that have weathered out of ore bodies can end up in stream gravels. C. are found in carrot-shaped structures called pegmatites. D. are brought from the mantle to the surface in magma that hardens into kimberlite

C

An unknown mineral scratches glass, has only average specific gravity, and shows no cleavage but does show conchoidal fracture. Which of the following could it be? A. halite B. mica C. talc D. quartz

D

When you scrape a mineral along a ceramic plate to observe the color of its powder, you are checking the physical property known as: A. luster. B. specific gravity. C. cleavage. D. streak.

D

Which of the following statements is FALSE? Formation of table salt: A. results in cubic crystals. B. is, in mineralogic terms, formation of the halide mineral halite. C. takes place when a solution has become saturated. D. is an example of solidification of a melt.

D

Which of the following statements is NOT true about quartz? A. Quartz has a fibrous crystal habit. B. Quartz does not have fracture. C. Quartz is softer than most minerals on Mohs scale. D. Quartz can be many different colors.

D